How to implement data stream processing using Stream API in Java?

The Stream API in Java allows working with data streams, providing a convenient and declarative way to process collections and other data sources. The main steps for working with streams:

1. Creating a stream from a collection or array, e.g., list.stream().
2. Applying intermediate operations (filter, map, sorted, etc.), which return a new stream and are not executed immediately.
3. Applying a terminal operation (forEach, collect, reduce, etc.), which triggers processing and returns a result.

Example:

import java.util.*;
import java.util.stream.*;

public class StreamExample {
    public static void main(String[] args) {
        List<String> names = Arrays.asList("Anna", "Bob", "Charlie", "David");

        // Get names longer than 3 characters, convert to uppercase, and print
        names.stream()
             .filter(name -> name.length() > 3)
             .map(String::toUpperCase)
             .forEach(System.out::println);
    }
}

This approach simplifies data processing, makes the code more readable, and allows easy parallelization of operations.